Rocket having barium release system to create ion clouds in the upper atmosphere

ABSTRACT

A chemical system for releasing a good yield of free barium (Ba*) atoms and barium ions (BA ) to create ion clouds in the upper atmosphere and interplanetary space for the study of the geophysical properties of the medium.

United States Patent [1 1 Paine et al.

[ ROCKET HAVING BARlUM RELEASE SYSTEM TO CREATEION CLOUDS IN THE UPPER ATMOSPHERE 221 Filed} Apr, 28, 1972" [211 Appl. No.2 248,761

Related US. Application Data [62] Division of Ser. No. 59,892, July 31, 1970.

[111 3,813,875 14 June 4,1974

[51 Int. Cl. F421) 13/46, F02k 9/00 [58] Field of Search 60/211, 214, 215, 225, 60/230, 39.46; 102/34.4, 34.5, 90

[ 5 6] References Cited UNITED STATES PATENTS 3,088,406 5/1963 Homer 60/225 3,145,530 8/1964 Sobey 60/225 3,182,593 5/1965 Seidner 60/225 Primary ExaminerBenjamin R. Padgett Attorney, Agent, or Firm-John R. Manning; Howard J. Osborn; Wallace .1. Nelson [57] ABSTRACT A chemical system for releasing a good yield of free barium (Ba) atoms and barium ions (BA*) to create ion clouds in the upper atmosphere and interplanetary space for the study of the geophysical properties of the medium.

4 Claims, 2 Drawing Figures [52] us. Cl 60/3946, 60/214, 60/215,

FIG 1 I00 N2H4 SATURATION LINE This is a division, of application Ser. No. 59,892 filed July 31, I970.

ORIGIN OF THE DISCLOSURE The invention described herein was made in the performance of work under a NASA contract and is subjectto the provisions of section 303 of the National Aeronautics and Space Act of 1958, Public Law 85-568 (72 Stat. 435; 42 USC 2457).

SPECIFICATION This invention relates generally to a chemical release system and relates in particular to a system for releasing barium in the vapor phase so that it can be ionized by solar radiation and also be excited to emit resonance radiation in the visible range. The ionized luminous cloud of barium then becomes a visible indication of magnetic and electric characteristics in space and allows determination of these properties over relatively large areas of space at a given time compared to rocket borne or orbiting instruments. For example, a geomagnetic field line could be illuminated by the present invention from pole-to-pole.

Presently, barium release systems are used to create ion clouds in'the upper atmosphere for the study of geophysical properties of the atmosphere. These known systems utilize a solid chemical system using a thermite mixtureof barium and copper oxide as the heat-producing reaction and an excess of bariumto be vaporized. This system is launched by a suitable rocket and, at a predetermined time, the ingredients are ignitedand released from a canister through a burst diaphragm and nozzle. The resulting barium cloud gives a brilliant color that can be observed and studied from earth to give indications of wind currents and the like. This known system of barium release has proved effective but is inherently of low efficiency in producing barium vapor yielding, in practice, only from 2 to 4 percent of the total chemical weight when actually up to 48 percent is available. In addition, the barium-copper oxide mixture is a fire hazard when mixing and pressing into the-canister and must be done under inert atmospheric conditions which proves timeconsuming and costly in operation. Also, little, if any, ionizati'on'takes place in this known system due to the initial heat generating reaction. g

It is therefore an object of the present invention to provide a new and novel barium release system for atmospheric and space studies.

Another object of the present invention is a system for releasing barium in the vapor phase so that it can be ionized by solar radiation and excited to emit resonance radiation in the visible range. 7

Another object of the present invention is a novel chemical mixture for releasing a good yield of free atoms and barium ions.

A further object of the present invention is a binary liquidhypergolic chemical release system in which barium is formed as a vapor at the time of release.

The foregoing and other objects are attained in one aspect of the present invention by providing a liquid fuel, in which barium salts are dissolved, and a high energy oxidizer which spontaneously ignites the fuel on contact. The barium release'is accomplished by impinging fuel and oxidizer jets in an open-ended com-' buation chamber which expels the reaction product gases or plasma and whichincludes the desired barium neutral atoms (Ba) and barium ions (321") as individual species.

A more complete appreciation of the invention and many of the attendant advantages thereof will be readily apparent as the same becomes better understood by reference to the following detailed description when considered in connection with the accompanying drawings wherein:

FIG. 1 is a schematic representation of the fuel and oxidizer tanks connected to an open-ended combustion chamber in a launch rocket for release of barium according to the present invention; and

FIG. 2 is a plot of triangular coordinates which defines the barium nitrate-barium chloride-hydrazine mixtures of the present invention.

Referring now to the drawings and more particularly to FIG. 1, there is shown a segment of a suitable carrier vehicle 10, such for example a rocket motor. Vehicle 10 is employed to carry fuel tank 11,.insulated oxidizer tank 13 and combustion chamber 15, along with the necessary instrumentation, from earth into the upper atmosphere or into interplanetary space. Fuel tank 1] is in fluid connection with combustion chamber 15 and oxidizer tank 13 is in fluid connection'with combustion chamber 15 byway of respective conduits l7 and 19. A pair of valves 21 and 23 are disposed within the respective conduits l7 and 19. Valves 21 and 23 are adapted to be selectively and simultaneously opened by a suitable battery-powered timing mechanism, radio signal, or the like, to release the pressurized fuel and oxidizer from tanks 11 and 13. The fuel and oxidizer then flow through conduits l7 and 19 and impinge upon each other through a centrally positioned manifold and suitable jets (not shown) in combustion chamber 15 where spontaneous ignition occurs. The reaction products are then expelled through the open ends of combustion chamber 15 as plasma which includes the desired barium neutral atoms and barium ions as individual species. v

The fuel utilized in fuel tank 11 is either hydrazine (N H or liquid ammonia (NH;,) while the oxidizer employed is selected from the group consisting of liquid fluorine (F2), chlorine trifluoride (ClF and oxygen difluoride (OF- Whenusing hydrazineas the fuel, barium may be dissolved therein as barium chloride, BaCI or barium nitrate, Ba(NO or a combination of the two. When using liquid ammonia as the fuel, bar- I ium metal may be dissolved therein. The combination found to produce the highest intensity of 821 and Ba resonance radiation in ground based tests involved a fuel of 16 percent Ba(NO;,) 17 percent BaCl and 67 percent MH; and as the oxidizer, the cryogenic liquid fluorine F and in which an oxidizer to fuel weight ratio was 1.32.

Other combinations of ingredients tested are set forth in Table I below:

v A IABLE l M A solubility study of various mixtures containing Ba(- N BaCl and N H was made at room temperature sys'em om'mum O/F and is shown in the triangular plot of FIG. 2. Seven so- Calculated lutions that were used in the tests enumerated in Table 5 I are indicated by reference letters in FIG. 2 as follows: mm may I 2-... 83.3% N H /ClF 2.36 68.0 26% B110, 74% NZHJCIF" 2.08 70.0 50% Ba(NO;.) 50% NH lClF 1.52 42.9% Ba(NO 57tl /r NZH4/CIF3 Ll) 50.0 .L 1 717, B c] 833 1 N l-l 16. u zh. 26% BaCl, 74% N H, 83.3% NIHJFZ L95 c. 21% B110, 9% Ba(NO;,) 70% N 11, 26% Bum,- d 17% Ban, 16% 1321 190,.) 67% N,H, 7 NzHtl z 1.7! e; 13% BaCl -2L5C4 Ba(NO;,),-65.5'/r N,Hi 21% suc 15 r. 9% B110 30% sumo 61% N,,H 9' utN mg. 42.9% BLl(NO 57.1 H 7()/, N H HI 57 68,5 1 f 2". .,;1. e;::";. M" 2 r 2' 4;. 17% B1101,- 16% Bfl(NO; 67% 19,117+ 1.31 621.1 13% 136C1 21.5% 561N011..- 20 (15.57 N H /F- 1.34 63.7 9% aimi- 4 i A mlxture below the Saturat1on Lme, that 1s toward 21 13 Saw 3111- I 04 m 7 the Ba(NO or BaCl corners contained a solid and a 42.9% 136 111 0,. solution phase whereas thesalts were 1n complete solu- STW t t/ 0-976 tion above the saturatlon line. 42.9% Ba(NO;,)- 25 e a t. 46.9 Qf fif 694 All fuel m1xtures or systems descr1bed were eas1ly 74% t/ F-2 1.22 handled except the 50 percent Ba(NO -5O percent 2*. .2 a. NH system. This system caused clogging of the feed valves due to precipitation of the Ba(NO In addition The conditions under which each of the combinations the light values obtained using this system was relalisted in Table I were tested were ambient and the pery 9 7 v, WV

w' alc l' ted b e uations set g i if fs% i i Z SqUbIiShed in In testmg of each of the fuel mixtures set forth in X" 1969 0 p p Table l the Ba light was greater than the Ba light for jr h h l ,l I d f Cturers Stated u a given oxidizer/fuel ratio in each of the mixtures. The C i. i f f d d are Set fortsin maximum light occurred in all systems at a point lorl tylorntbelvar ous c emica S emp 0Y cated between the stoichiometric O/F and 3 percent 9 less than the stoichiometric O/F. The stoichiometric O/F is defined as being equivalent to the oxidizer to TABLE I] 40 fuel weight ratio in a balanced equation assuming the g salt is converted to free Ba, F to HF, Cl to HCl and O l' to H O. For example, one system tested had an O/F N. .H, Olin Mathieson Chemical wet-11616111011146 ratio of 142 grams oxidizer per 100 grams fuel or l f' Lake Charles Z;} 1.42/ 1.00. If the barium 1s assumed to be converted to .OUISHIDH l 2 NH;I Air Products and Chemicals Technical Grade BaF2 the stolcblometnc 0: 15 Smce the Allentown. P11. greatest light output 1n all cases occurred w1th O/F less n Reagan Grade than stoichiometric it is apparent that little of the Ba lhilllpsburg. NJ. 131111901)2 J. 'r. Baker & Cit. Reagent Grade was combmed as BaF or BaCl This was confirmed by Phillipshurg. NJ. t a a F2 Air Products 8; Chemicals 937' EECELQELrPJIL3lYmSLSm fl- ""H' Allentown. P11. 50 1 CIF" Allied Chemim] C04 2 In Table II the vanous systemsare listed in decreas- Baton Rouge. La. mg llght output or relat1ve light intenslty as measured 05 by phototubes 1n milhvolts, thereby 1nd1catmg the rela- Baton Rouge. L11.

2 m k twmyield-mm TABLE III SYSTEM MAXIMUM RELATIVE (percent weight for fuel) Ba 5535 A 1311+ 4554 A 17% BaCl -lfili Ba(No .,),-67% N,H,/F 27600 11x00 13% Hafi -21.5% Ba(NO -65.5'/r N m/F 23600 8340 21% Bac -9% [amo g-70% N,H,/F., 20600 9100 9% Bac -30% Ba(NO;,),-6l% N H r, 16600 5970 26% Bac -74% N,H./F 16600 6520 26% Hafi -74% N,H4/OF, 111100 2100 16.7% Hafi -83.3% 61 11, 9100 3350 42.9% Ba(NO;,) -57.l/1 N HJF, 9000 11400 42.9% Ba(NO;,) -57.l/r NZH4/OF, 7300 1330 42.9% Ba(NO ),-57.l'/( N,H /CIF,, 663 94 50% Bu(No .,),-50% NHHICIF" 221 44 he tie asst;10515151166755 iadhy tam that the 17 percent BaCl -16 percent Ba(NO -67 percent taining 8.52 weight percent barium was estimated to be 68.1 percent ionized. Also since this system had the largest relative light intensity it would be expected to give the greatest amount of Ba and Ba and would appear to be the optimum system for a barium payload. In all systems tested it was found that the relative light reached a maximum'at the O/F corresponding to the stoichiometric equation yielding barium as one of the reaction products and that the relative light output was sensitive to the O/F. Moving to either side of the optimum O/F caused a sharp decrease in relative light.

In vacuum tests the ignition of each system tested was smooth and like the ambient tests, took place in the combustion chamber. The rapid expansion in vacuum caused a decreased atom and ion density in the luminous flame which caused the light intensity to be about [/37 to l/50 the intensity measured in ambient tests. The percentage ionization was approximately the same for vacuum and ambient tests.

The operation ofthe invention is now believed apparent. 'lnitially, fuel tank 11 is charged with the fuel containing the desired quantity of dissolved barium salt and pressurized with helium. The fuel tank pressure may be in the range of 6.89 to 20.06 X Newton/meter? Oxidizer tank 13 is also charged with the appropriate oxidizer and pressurized. Cryogenic oxidizers such as OF and F are condensed from gases in the closed oxidizer tank which must be maintained enclosed in a liquid nitrogen bath. The oxidizer feed valve 23 and conduit 19 must also be maintained at liquid nitrogen temperature with a liquid nitrogen jacket when employing a cryogenic oxidizer.

The noncryogenic oxidizer, ClF may be pressurized into the closed oxidizer tank 13 from a supply bottle with super dry nitrogen.

Combustion chamber 15 is formed of stainless steel, aluminum, or the like F compatible metals and is internally partitioned by the manifold, not shown. The conduits l7 and 19 terminate in a manifold having injector orifices (not shown) mounted 90 to each other within each end of chamber 15 and sized for pressure drops of 5.24 to 10.2 X 10 Newton/meter acrossthe orifice. Fuel and oxidizer flows are in the range of 2.05 to 6.82 Kg/sec each. The entire system is carried into the upper atmosphere or interplanetary space by rocket vehicle 10 where, in response to a suitable signal, timing mechanism or the like, valves 2] and 23 may be selectively opened and closed and the pressurized liquid fuel and oxidizer will flow through conduits l7 and 19 into combination unit 15. When the hypergolic liquids impinge upon each other, they spontaneously ignite to expel reaction product gases or plasma including the highly luminous barium neutral atoms'and barium ions as individual species. All'of the barium reaching the combustion chamber is vaporized and released through the opposite ends thereof so that a high yield efficiency is obtained. The resulting high flame temperature, approximately 4,000K., and some as yet notdetermined chemical activation, produces a relatively large amount of barium ions in the flame which is a highly desirable condition. It has been estimated from spectroscopic measurements that the degree of ionization may be as high as 75 percent in the released plasma in comparison to being on the order of 1 percent for the previously used Ba-CuO solid system which depends almost entirely on solar photoionization, a time-dependent phenomena which further reduces the usable barium yield of this known system.

Thus, it is readily apparent that the present invention provides an inherently more efficient process of producing barium clouds wherein the degree of ionization in the released plasma is much greater. The selectively opening and closing of valves 21 and 23 gives the possibility of a payload with multiple releases permitted due to the start and stop capabilities of the liquid system. Also, the liquid system of the present invention gives the possibility. of controlling rates so that a trailtype release can be obtained as well as a point-source type. In addition, the liquid system of the present invention effects the formation of barium atoms'and ions at the time of combustion and expansion at high temperatures and results in little opportunity for the barium to condense during release.

There are obviously many variations and modifications to the present invention that will be readily apparent to those skilled in the art without departing from the spirit or scope of the disclosure or from the scope of the claims.

What is claimed as new and desired to besecured by Letters Patent of the United States is:

1. Apparatus for releasing free barium atoms and barium ions in the upper atmosphere to emit resonance radiation in the form of a luminous cloud comprising:

arocket vehicle capable of being launched into the upper atmosphere of earth,

a longitudinally configured payload carried by said rocket vehicle, I

said payload including:

a fuel tank disposed at one end of the payload,

an oxidizer tank disposed at the opposite end of the payload, and an open ended combustion chamber diametrically disposed intermediate said fuel tank and said oxidizer tank and with both ends thereof being open to the atmosphere, conduit means connecting said fuel tank and said oxidizer tank to'said combustion chamber, valve means disposed in said conduit means for selectively permitting fluid flow from said fuel tank and said oxidizer tank into said combustion chamber,

a liquid fuel having a quantity of barium salts dissolved therein disposed within said fuel tank,

a liquid oxidizer disposed in said oxidizer tank,

said liquid fuel and said liquid oxidizer having the inherent chemical property characteristics of undergoing a hypergolic reaction upon contact with each other whereby, when said valve means permit flow of said liquid fuel and said liquid oxidizer into said combusion chamber the resulting hypergolic reaction releases a high yield of luminous barium atoms and barium ions.

2. The apparatus of claim 1 wherein the liquid fuel is selected from the group consisting of hydrazine and liquid ammonia.

3. The apparatus of claim 2 wherein the barium salts contained in the liquid fuel is a mixture of barium chloride and barium nitrate.

4. The apparatus of claim 1 wherein the liquid oxidizer is selected fromthe group consisting of F OF and ClF 

2. The apparatus of claim 1 wherein the liquid fuel is selected from the group consisting of hydrazine and liquid ammonia.
 3. The apparatus of claim 2 wherein the barium salts contained in the liquid fuel is a mixture of barium chloride and barium nitrate.
 4. The apparatus of claim 1 wherein the liquid oxidizer is selected from the group consisting of F2, OF2 and ClF3. 